fyi1183

11 ms·

91.
by fyi1183 9y ago
To play devils advocate, the success of Asian Americans and Jews could also be explained by genetics. My own biases as well as basic knowledge of the respective cultures makes me fairly certain that it's culture in both cases rather th
92.
by fyi1183 9y ago
Those visible effects (caches being primed by speculative execution) are desirable in many cases though, so it's misleading to say the processor is wrong.
93.
by fyi1183 9y ago
You don't need to model the timing though. What I'm saying with the type system comment is this: the cache side effects of speculation are desirable most of the time but not always. We should find a way to model data sensitivity i
94.
by fyi1183 9y ago
If you don't feel overwhelmed enough by the misprediction variant of Spectre yet, consider that the cache side effect of speculation is actually desirable in most normal cases, because it helps prime caches with data that is likely t
95.
by fyi1183 9y ago
Well, there seems to be a lot of hysteria right now. You mention speculation-based side effects in general, but keep in mind that only data-dependent side effects matter. There aren't that many of those outside the memory system, if
96.
by fyi1183 9y ago
The linked advisory 254 claims that SP2 is limited to code after bounds checks and similar when SMEP is used. This is incorrect: the BTB can be poisoned to speculatively jump anywhere in the text segment of the supervisor.
97.
by fyi1183 9y ago
The solution may lie in a new "non-speculative load“ instruction that delays execution until preceding branches are confirmed. This would allow keeping the performance of speculative execution in the vast majority of cases, while also
98.
by fyi1183 9y ago
Honestly, you probably don't even need the barrier in your example. Getting data[a] into the cache is no information leak if the attacker already knows a. That's why the example in the Spectre paper uses an additional level of ind
99.
by fyi1183 9y ago
I agree that we'll probably see new attacks in this area for a long time. That said, the main new ingredient of Spectre seems to be the idea that userspace can poison the branch target buffer to cause speculative execution of arbitrary
100.
by fyi1183 9y ago
What people usually mean by demand in this context is effective demand, which means people offering money in exchange for goods. That can be increased quite easily, and it makes perfect sense, because people/businesses will produce mor